Chemical vapor deposition apparatus

Abstract

The present invention relates to a chemical vapor deposition apparatus and, more specifically, to a chemical vapor deposition apparatus that can be cleaned by removing particles or the like adhered to the bottom and inner walls of a processing space during a process of depositing a gallium oxide (Ga2O3) film or the like on a substrate.

Description

chemical vapor deposition device

[0001] The present invention relates to a chemical vapor deposition apparatus, and more specifically, to a chemical vapor deposition apparatus capable of removing and cleaning particles attached to the floor and inner walls of a processing space during a process of depositing a gallium oxide (gallium oxide: Ga2O3) film on a substrate.

[0002] Demand for power semiconductor devices has been rapidly increasing recently, and the related market is expected to continue to grow.

[0003] In power semiconductors, gallium oxide (Ga2O3) power semiconductors have recently been attracting attention, following SiC and GaN. Gallium oxide offers superior withstand voltage characteristics compared to conventional silicon-based substrates, as well as superior reliability and stability.

[0004] However, when producing such gallium oxide power semiconductors, foreign substances such as particles may adhere to the inside of the chamber of the deposition device, and these foreign substances reduce the productivity of the deposition device producing the power semiconductors.

[0005] The present invention aims to solve the above problems by providing a chemical vapor deposition apparatus capable of effectively cleaning foreign substances such as particles inside a chamber.

[0006] The above object of the present invention can be achieved by a chemical vapor deposition apparatus characterized by comprising a chamber, a lower plate provided inside the chamber and having a susceptor for mounting a substrate thereon, forming a processing space for the substrate, a first heater provided at the lower portion of the susceptor or around the susceptor and heating the substrate or the susceptor, and a second heater provided at the lower portion of the lower plate and heating the lower plate.

[0007] Here, the second heater may be positioned so as not to overlap with the first heater at the lower portion of the lower plate.

[0008] Additionally, the first heater and the second heater may have different heating methods. For example, the first heater may be configured as an induction heater, and the second heater may be configured as a resistance heater or a halogen lamp.

[0009] Meanwhile, when the second heater is configured as a resistance heating heater, heat of the second heater can be transferred to the lower plate by conduction.

[0010] Furthermore, the second heater may be placed in direct contact with the lower plate, or a heat transfer plate may be further provided between the second heater and the lower plate.

[0011] In addition, an upper cover provided on the upper part of the lower plate and a third heater provided on the outside of the upper cover may be further provided.

[0012] In this case, the third heater may be composed of a resistance heater or a halogen lamp.

[0013] Meanwhile, a heat-insulating member may be further provided inside the chamber to surround the lower plate, the first heater, and the second heater.

[0014] Additionally, an additional heat-blocking member may be provided at the bottom of the first heater and the second heater.

[0015] Furthermore, an insulating member may be further provided between the first heater and the lower plate.

[0016] In this case, the heat-blocking member may be composed of carbon felt or graphite felt.

[0017] According to the present invention having the above-described configuration, the lower plate constituting the processing space and further the upper cover can be heated to a cleaning temperature to effectively remove foreign substances such as particles inside the chamber.

[0018] FIG. 1 is a side cross-sectional view showing the internal configuration of a chemical vapor deposition apparatus according to one embodiment of the present invention;

[0019] Figure 2 is a partial perspective view showing the first heater and the second heater;

[0020] Figure 3 is a side cross-sectional view showing the internal configuration of a chemical vapor deposition apparatus according to another embodiment of the present invention.

[0021] Figure 4 is a plan view showing the results of an experiment to confirm the particle removal effect by the cleaning process of the present invention.

[0022] FIG. 5 is a side cross-sectional view showing the internal configuration of a chemical vapor deposition apparatus according to another embodiment of the present invention.

[0023] FIG. 6 is a cross-sectional side view illustrating the internal configuration of a chemical vapor deposition apparatus according to another embodiment of the present invention.

[0024] Hereinafter, the structure of a chemical vapor deposition apparatus according to an embodiment of the present invention will be examined in detail with reference to the drawings.

[0025] FIG. 1 is a cross-sectional side view showing the internal configuration of a chemical vapor deposition apparatus (1000) according to one embodiment of the present invention, and FIG. 2 is a partial perspective view showing a first heater (330) and a second heater (332, 334).

[0026] Referring to FIGS. 1 and 2, the chemical vapor deposition apparatus (1000) may include a chamber (100), a lower plate (320) provided inside the chamber (100) and having a susceptor (324) on which a substrate (W) is mounted, forming a processing space (312) for the substrate (W), a first heater (330) provided at the lower portion of the susceptor (324) or around the susceptor (324) to heat the substrate (W) or the susceptor (324), and a second heater (332, 334) provided at the lower portion of the lower plate (320) to heat the lower plate (320).

[0027] A receiving space (110) is provided inside the chamber (100), and various components can be provided therein.

[0028] Additionally, a gas supply unit (200) may be connected to one side of the chamber (100). The gas supply unit (200) may supply various process gases, purge gases, or cleaning gases toward the processing space (312).

[0029] Here, the aforementioned processing space (312) may be formed by the lower plate (320). Specifically, an upper cover (310) may be provided on the upper portion of the lower plate (320), and the processing space (312) may be defined as a space between the lower plate (320) and the upper cover (310). The upper cover (310) may have an appropriate shape or structure capable of forming the processing space (312) between itself and the lower plate (320), and is not particularly limited thereto. In addition, the upper cover (310) may be manufactured as a separate member from the lower plate (320) and then assembled, or the upper cover (310) may be formed integrally with the lower plate (320).

[0030] Meanwhile, the gas supply unit (200) may be provided with a gas inlet pipe (220) that extends from the outside of the chamber (100) to the inside of the chamber (100) and is connected to the processing space (312). A supply port (210) through which various gases are supplied may be formed in the gas inlet pipe (220) located outside the chamber (100).

[0031] The chemical vapor deposition apparatus (1000) according to the present invention can be used to produce power semiconductors, and in particular, can be used to produce gallium oxide (gallium oxide: Ga2O3) power semiconductors.

[0032] In this case, a process gas or the like is supplied from the side of the processing space (312) by the gas supply unit (200) to induce a laminar flow of gas inside the processing space (312) so that a gallium oxide thin film can be grown on the upper surface of the substrate (W).

[0033] Meanwhile, when depositing a gallium oxide thin film on the upper surface of the substrate (W), the process temperature may be a high temperature corresponding to approximately 1000 degrees Celsius. Accordingly, the upper cover (310) and the lower plate (320) that partition the processing space (312) may be made of quartz or the like.

[0034] In this case, a susceptor (324) on which the substrate (W) is mounted can be mounted on the lower plate (320).

[0035] For example, a concave portion (322) may be formed in the lower plate (320), and the susceptor (324) may be inserted and placed in the concave portion (322).

[0036] Meanwhile, the susceptor (324) may be rotatably provided on the lower plate (320). That is, a nozzle (not shown) for supplying floating gas or the like toward the lower surface of the susceptor (324) may be provided in the concave portion (322) to rotate the susceptor (324). During a process for the substrate (W), the substrate (W) may be rotated by the rotation of the susceptor (324), so that the process gas or the like supplied from the side may react uniformly on the entire surface of the substrate (W).

[0037] In addition, although FIGS. 1 and 2 illustrate a so-called 'single-sheet type' in which one substrate (W) is mounted, as an example, the present invention is not limited thereto, and for example, it is also possible to configure a so-called 'batch type' in which a plurality of substrates are mounted on the susceptor (324).

[0038] A gas exhaust pipe (400) through which gas of the processing space (312) is exhausted may be connected to the other side of the processing space (312). The gas exhaust pipe (400) may extend to the outside of the chamber (100) to exhaust gas of the processing space (312) to the outside of the chamber (100).

[0039] Meanwhile, the chemical vapor deposition device (1000) may be equipped with a first heater (330) for heating the substrate (W) or susceptor (324) to a process temperature.

[0040] The first heater (330) may be positioned at the bottom of the susceptor (324) or around the susceptor (324). For example, the first heater (330) may be positioned at the bottom of the lower plate (320) and may be positioned at the bottom of the concave portion (322).

[0041] In addition, it can be said that the first heater (330) is placed at the lower portion of the lower plate (320) and the lower portion of the susceptor (324). As a result, the substrate (W) or the susceptor (324) can be heated more effectively by the first heater (330).

[0042] Meanwhile, as described above, during the processing process for the substrate (W), gallium oxide (gallium oxide: Ga2O3) particles and the like may be formed on the upper surface of the lower plate (320) forming the processing space (312). In addition, particles and the like may also be formed on the inner surface of the upper cover (310) forming the processing space (312). These particles are generated during the processing process for the substrate (W) and may be attached to the base and ceiling forming the processing space (312) and affect the substrate (W). Therefore, it is necessary to remove the particles, and these particles can be removed at a temperature of approximately 1000 degrees Celsius or higher, preferably at a temperature of 1300 degrees Celsius or higher.

[0043] The chemical vapor deposition apparatus (1000) according to the present invention may be provided with a second heater (332, 334) for heating the lower plate (320) at the lower portion of the lower plate (320) to remove the particles.

[0044] In this case, the second heater (332, 334) is positioned so as not to overlap with the first heater (330) at the bottom of the lower plate (320), and can be positioned in an area other than the area where the first heater (330) is positioned.

[0045] For example, if the first heater (330) is arranged in the central portion based on the flow direction of the process gas at the bottom of the lower plate (320), the second heaters (332, 334) may be arranged on both sides of the first heater (330), that is, upstream and downstream of the first heater (330) based on the flow direction of the process gas, respectively. In addition, if the first heater (330) is formed in a circular shape or the like corresponding to the susceptor (324) or the substrate (W), the second heaters (332, 334) may be arranged to cover the entire area except for the area where the first heater (330) is arranged at the bottom of the lower plate (320).

[0046] In this case, the first heater (330) and the second heater (332, 334) may be configured as heaters having different heating methods. For example, the first heater (330) described above may be configured as an induction heating heater, and the second heater (332, 334) may be configured as a resistance heating heater.

[0047] In the above-described configuration, the temperature of the substrate (W) or susceptor (324) can be heated to a process temperature by the first heater (330) configured as an induction heater.

[0048] The shape of the induction heating coil constituting the first heater (330) may be a circular or rectangular shape, so-called 'pancake type'. Since the induction heating coil can be used semi-permanently after installation, it has advantages in terms of maintenance and equipment operation costs.

[0049] In addition, the susceptor (324) can be manufactured using, for example, graphite, silicon carbide coated graphite (SiC coated graphite), TaC coated graphite (Tac coated graphite), or silicon carbide material using a CVD sintering method. This can increase thermal stability and thermal conductivity, efficiently heat the substrate, and reduce power consumption.

[0050] Furthermore, the susceptor (324) is made of graphite and can be heated by the first heater (330) configured as an induction heater.

[0051] However, as described above, the lower plate (320) is made of a material other than graphite, such as quartz, and therefore it is difficult to heat it using an induction heater. Therefore, the second heater (332, 334) may be configured as a heater having a different heating method from the first heater (330), and may be configured as a resistance heater, for example.

[0052] Meanwhile, in the drawing, the second heater (332, 334) is depicted as being spaced apart from the lower surface of the lower plate (320), and in this case, the heat of the second heater (332, 334) can be transferred to the lower plate (320) by convection or radiation.

[0053] In addition, if the second heater (332, 334) is configured as a resistance heater, although not shown in the drawing, the second heater (332, 334) may directly contact the lower surface of the lower plate (320) and heat the lower plate (320) by conduction.

[0054] Furthermore, a heat transfer plate (not shown) may be provided between the lower plate (320) and the second heater (332, 334).

[0055] The lower plate (320) and the second heater (332, 334) may be connected to each other by the heat transfer plate, or the heat transfer plate may be arranged to be spaced apart from the lower plate (320) and the second heater (332, 334).

[0056] In this case, the heat of the second heater (332, 334) can be transferred to the lower plate (320) through the heat transfer plate to enhance the heating effect. Here, the heat transfer plate can be made of a metal with high thermal conductivity, and the material is not particularly limited.

[0057] When the lower plate (320) and the second heater (332, 334) are connected to each other by the heat transfer plate, the heat of the second heater (332, 334) is transferred to the lower plate (320) by conduction, thereby increasing the heat transfer efficiency compared to convection and radiation, thereby reducing power consumption and shortening the operating time of the heater.

[0058] Furthermore, when the lower plate (320) and the second heater (332, 334) are connected to each other by the heat transfer plate, there is an advantage in that the temperature of the lower plate (320) can be directly measured by placing a thermocouple or the like on the heat transfer plate.

[0059] Therefore, when cleaning the chamber (100), the lower plate (320) can be heated to the cleaning temperature by the second heater (332, 334).

[0060] Additionally, although not shown in the drawing, the second heater may be configured as a halogen lamp. In this case, the light energy from the halogen lamp may be absorbed by opaque particles, etc. attached to the lower plate (320), thereby concentrating the heat energy on the particles, etc. to be removed. In addition, when the lower plate (320) is made of a quartz material, the light energy from the halogen lamp may also heat the upper cover (310) by transmitting through the lower plate (320).

[0061] Meanwhile, although not shown in the drawing, a configuration in which a heating plate made of graphite is provided on the lower surface or bottom of the lower plate (320), and both the first heater (330) and the second heater (332, 334) are provided as induction heating coils is also possible. That is, a heating plate made of graphite is provided on the lower surface of the lower plate (320) made of quartz, so that the lower plate (320) can be heated by induction heating.

[0062] As described above, when the first heater (330) is configured as an induction heater and the second heater (332, 334) is configured as a resistance heater, noise may be generated due to magnetic field interference caused by the AC power supplied to the first heater (330) and the DC power supplied to the second heater (332, 334). To remove such noise, a noise filter (not shown) may be connected to the second heater (332, 334). For example, a power supply unit (not shown) that supplies power to the second heater (332, 334) may be further provided, and a noise filter may be connected to the power supply unit.

[0063] The first heater (330) and the second heater (332, 334) may be installed inside the chamber (100) by a support member not shown in the drawing, or may be connected to and mounted on the lower plate (320). The installation structure of the first heater (330) and the second heater (332, 334) is not specifically limited.

[0064] Meanwhile, FIG. 3 is a cross-sectional view illustrating the internal configuration of a chemical vapor deposition apparatus (2000) according to another embodiment of the present invention.

[0065] Referring to FIG. 3, as described above, foreign substances such as particles may be attached to the inner wall of the upper cover (310), and in order to remove such foreign substances, a third heater (340) may be provided that is arranged on the outside of the upper cover (310) and surrounds the upper cover (310).

[0066] The third heater (340) may be arranged to surround the upper portion of the upper cover (310), or may be arranged to surround the entire outer surface of the upper cover (310). In addition, the third heater (340) may be installed separately from the second heater (332, 334) described above, or the third heater (340) may be arranged to be connected to the second heater (332, 334).

[0067] For example, if the upper cover (310) and the lower plate (320) are configured as a tube-shaped structure in which both sides of the upper cover (310) and the lower plate (320) are connected to each other, the third heater (340) and the second heaters (332, 334) may be arranged in a form that continuously wraps the tube-shaped structure in a spiral shape. In this case, the first heater (330) described above may be excluded.

[0068] In addition, the third heater (340) may be configured as, for example, a resistance heating heater or a halogen lamp, but is not limited thereto.

[0069] If the third heater (340) is configured as a resistance heater, it may be arranged in the same manner as the second heater (332, 334) discussed above.

[0070] For example, the third heater (340) may be positioned spaced apart from the upper cover (310) to heat the upper cover (310) by convection or radiation. In addition, the third heater (340) may be in direct contact with the upper cover (310) or may be connected to each other by a heat transfer plate to transfer heat to the upper cover (310) by conduction.

[0071] Meanwhile, by heating the lower portion of the lower plate (320) by the second heater (332, 334) described above, and also heating the upper portion or side of the upper cover (310) by the third heater (340), foreign substances attached to the upper surface of the lower plate (320) and the inner wall of the upper cover (310) can be more effectively removed.

[0072] Hereinafter, a cleaning process for removing foreign substances such as particles attached to the floor or inner wall of the processing space (312) in a chemical vapor deposition device (1000, 2000) having the aforementioned configuration will be described.

[0073] First, during the cleaning process of the chamber (100), the lower plate (320) or the lower plate (320) and the upper cover (310) can be heated to a cleaning temperature.

[0074] The above cleaning temperature corresponds to a temperature capable of removing the aforementioned foreign substances, which is approximately 1000 degrees Celsius or higher. However, in order to increase the efficiency of removing foreign substances through the cleaning process and reduce the time of the cleaning process, the cleaning temperature may preferably correspond to approximately 1300 degrees Celsius or higher.

[0075] In this case, the lower plate (320) is heated by the second heater (332, 334) described above. In addition, the third heater (340) can be driven together to heat the upper cover (310) as well. As a result, the lower plate (320) or the lower plate (320) and the upper cover (310) can be heated to a cleaning temperature.

[0076] Next, cleaning gas can be supplied to the processing space (312). In this case, the cleaning gas can be supplied to the processing space (312) through the gas supply unit (200). The cleaning gas can be supplied simultaneously with, prior to, or after the operation of the second heater (332, 334) or the second heater (332, 334) and the third heater (340).

[0077] The above cleaning gas may be composed of, for example, hydrogen (H2), but is not limited thereto.

[0078] Accordingly, by heating the lower plate (320) or the lower plate (320) and the upper cover (310) to a cleaning temperature and supplying cleaning gas, foreign substances attached to the upper surface of the lower plate (320) or the inner wall of the upper cover (310) can be removed.

[0079] The removed foreign substances, etc. can be discharged to the outside of the chamber (100) through the gas exhaust pipe (400).

[0080] Figure 4 illustrates the results of an experiment to verify the particle removal effect of the aforementioned cleaning process. Figure 4 (A) illustrates a sapphire substrate surface with gallium oxide powder attached, and Figure 4 (B) illustrates a sapphire substrate surface that has undergone the aforementioned cleaning process.

[0081] Referring to Fig. 4 (A), it can be seen that gallium oxide powder is attached to the surface of the sapphire substrate. When the sapphire substrate is cleaned by supplying hydrogen at a cleaning temperature of 1300 degrees Celsius for approximately 30 minutes, it can be confirmed in Fig. 4 (B) that the gallium oxide powder is removed from the surface of the sapphire substrate.

[0082] Meanwhile, Fig. 5 is a cross-sectional side view illustrating a chemical vapor deposition apparatus (3000) according to another embodiment of the present invention. In Fig. 5, the same reference numbers are used for the same components as in the aforementioned embodiment.

[0083] Referring to FIG. 5, the chemical vapor deposition device (3000) may adopt a so-called dual chamber structure. That is, an inner chamber (300) may be further provided inside the chamber (100) described above, and the lower plate (320), first heater (330), and second heaters (332, 334) described above may be provided inside the inner chamber (300).

[0084] Additionally, the upper cover (310) and the third heater (340) may be provided on the inside of the inner chamber (300).

[0085] By adopting the so-called double chamber structure in this way, the possibility of particle contamination of the substrate (W) can be reduced, and the treatment process and cleaning process for the substrate (W) can be performed more efficiently.

[0086] The aforementioned gas inlet pipe (220) may be connected to the processing space (312) by penetrating the inner chamber (300). In addition, the gas exhaust pipe (400) may extend from the rear end of the processing space (312) to the outside of the chamber (100) by penetrating the inner chamber (300).

[0087] In this embodiment, the inner chamber (300) may function as a heat-blocking member. That is, the inner chamber (300) is arranged to surround the lower plate (320), the upper cover (310), the first heater (330), the second heaters (332, 334), and the third heater (340), and may be composed of carbon felt, graphite felt, or the like. Alternatively, the inner chamber (300) may be composed of graphite-coated carbon felt or carbon-coated graphite felt, or the like.

[0088] In this way, when the inner chamber (300) or the heat blocking member is provided, the heat from the first heater (330), the second heater (332, 334), and the third heater (340) is not radiated to the outside of the inner chamber (300), so that the processing space (312) can be heated more effectively.

[0089] Meanwhile, Fig. 6 is a cross-sectional side view illustrating a chemical vapor deposition apparatus (4000) according to another embodiment of the present invention. In Fig. 6, the same reference numbers are used for the same components as in the aforementioned embodiment.

[0090] Referring to FIG. 6, an additional heat blocking member (302) may be further provided below the first heater (330) and the second heaters (332, 334). The additional heat blocking member (302) may be provided on the upper portion of the base of the chamber (100) as illustrated in the drawing.

[0091] The heat radiation to the base of the chamber (100) by the susceptor (324), the first heater (330), and the second heater (332, 334) can be blocked by the additional heat blocking member (302).

[0092] The above additional heat-blocking member (302) is depicted as a separate member from the inner chamber (300), but may be provided as a single component integral with the inner chamber (300).

[0093] Additionally, an insulating member (304) may be further provided on the upper portion of the first heater (330). More specifically, the insulating member (304) may be positioned between the first heater (330) and the lower plate (320).

[0094] The above insulating member (304) is not positioned above the second heater (332, 334), but is positioned only above the first heater (330). Since the first heater (330) is configured as an induction heater, even if the insulating member (304) is positioned, the lower plate (320) and the susceptor (324) can be heated by the first heater (330).

[0095] However, the heat of the lower plate (320) and the susceptor (324) can be blocked by the insulating member (304) to block heat radiation to the base of the chamber (100).

[0096] Of course, this insulating member (304) can also be applied to the embodiments of FIGS. 1, 3, and 5 described above.

[0097] Meanwhile, the description of the lower plate (320), the upper cover (310), the first heater (330), the second heater (332, 334), and the third heater (340) is similar to the above-described embodiment, so a repeated description is omitted.

[0098] While the present invention has been described above with reference to preferred embodiments, those skilled in the art will appreciate that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention as defined in the claims below. Therefore, any modified implementation that fundamentally includes the elements of the claims should be considered within the technical scope of the present invention.

[0099] According to the present invention, foreign substances such as particles inside the chamber can be effectively removed by heating the lower plate constituting the processing space and further the upper cover to a cleaning temperature.

Claims

1. Chamber; A lower plate provided inside the chamber, on which a susceptor for mounting a substrate is mounted, and which forms a processing space for the substrate; A first heater provided at the lower part of the susceptor or around the susceptor to heat the substrate or the susceptor; and A chemical vapor deposition apparatus characterized by comprising a second heater provided at the lower portion of the lower plate and heating the lower plate.

2. In paragraph 1, A chemical vapor deposition apparatus characterized in that the second heater is positioned so as not to overlap with the first heater at the lower portion of the lower plate.

3. In paragraph 1, A chemical vapor deposition device characterized in that the first heater and the second heater have different heating methods.

4. In paragraph 1, A chemical vapor deposition apparatus characterized in that the first heater is configured as an induction heating heater and the second heater is configured as a resistance heating heater or a halogen lamp.

5. In paragraph 4, If the second heater is configured as a resistance heating heater, A chemical vapor deposition apparatus characterized in that the heat of the second heater is transferred to the lower plate by conduction.

6. In paragraph 5, The second heater is placed in direct contact with the lower plate, or Or a chemical vapor deposition apparatus characterized in that it further comprises a heat transfer plate between the second heater and the lower plate.

7. In paragraph 1, A chemical vapor deposition apparatus characterized by further comprising an upper cover provided on the upper portion of the lower plate and a third heater provided on the outside of the upper cover.

8. In paragraph 7, A chemical vapor deposition apparatus characterized in that the third heater is composed of a resistance heating heater or a halogen lamp.

9. In paragraph 1, Equipped inside the above chamber A chemical vapor deposition apparatus characterized in that it further comprises a heat-insulating member surrounding the lower plate, the first heater, and the second heater.

10. In paragraph 9, A chemical vapor deposition apparatus characterized in that an additional heat-blocking member is further provided at the lower portion of the first heater and the second heater.

11. In paragraph 1, A chemical vapor deposition apparatus characterized in that an insulating member is further provided between the first heater and the lower plate.

12. In paragraph 7, A chemical vapor deposition device characterized in that the above heat-blocking member is composed of carbon felt or graphite felt.

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